Insulating structure



, T. s. DONNELLY 2,327,303

INSULATING STRUCTURE Filed OCT.. 13, 1941 Aug. 17, 1943.

vnventor Patented ug. 17, 1943 UNITED STATES PATENT OFFICE i 2,327,303 l y INSULATING STRUCTURE Thomas S. Donnelly, Detroit, Mich. Application October 13, 1941, Serial No. 414,769 6 Claims. (Cl. 219-8) My invention relates to a new and useful improvement in an insulating structure adapted primarily for use on electrode holders used in arc welding and similar operations. Among the types vof electrode holders used is one in which there is a pair of separable jaws normally spring held in closed relation so as to grip an electrode therebetween. In order to spring these jaws apart a rockable stirrup is used through which one of the jaws is projected so that the base of the stirrup lies between the jaws and serves as a cam when the stirrup is rocked. Projecting outwardly from the upper side of the stirrup is a prong or rod whereby the stirrup may be rocked against the tension of the spring jaws to force the same apart. In some uses of electrode holders it is desirable that no metal parts be exposed and to accomplish this, insulation is resorted to. In the present structure the prong or rod is embraced by a tubular piece of insulating material formed from fibre, an asbestos composition or the like, the purposes being to insulate against electric conductivity and also against heat.

The present invention embodies a means for insulating the outer face of the side bars of the stirrup and the outer face of the top bar of the stirrup. Various means have been resorted to forinsulating this stirrup and experience has shown that the insulation for the side bars and the top bar, because it is subjected to high heat, frequently is destroyed and has to be replaced.

The present invention has as its object a means of insulating a stirrup of this nature in such a manner that the insulation will be held in position and be readily and easily removable and replaceable.

Another object of the invention is the provision of L-shaped members each adapted for covering the outer face of one of the side bars and a portion of the top bar of the stirrup and provided with a notch for accommodating the outwardly projecting rod or prong.

Another object of the invention is ther provision in an electrode holder, of means for insulating a stirrup of this kind in such a manner that the insulating material may be easily secured in position and prevented from undue movement while in use.

Another object of the invention is the provision in an electrode holder of an insulating member having a pair of angularly directed por-` tions provided with openings formed therein.

Other objects will appear hereinafter. The invention consists in the combination and arrangement of parts hereinafter describedand E ly from the forward claimed andY it is recognized that departures and variations may be made from the detail of structure without departing from the spirit of the invention and it is intended that such variations shall be embraced in claims forming a part hereof.

Forming a part of the speciiication is a drawing in which:

Fig. l is a side elevational view of an electrode holder showing the invention applied, with parts of the holder broken away and parts shown in section.

Fig. 2 is a sectional of Fig. 1.

Fig. 3 is a sectional view taken on line 33 of Fig. 1.

Fig. 4 is a perspective member.

Fig. 5 is a perspective view of the insulating member shown in Fig. 4, divided.

Fig. 6 is a'view similar to Fig. 2 illustrating the undivided insulating member in use.

For the purposes of illustration I have indicated, in Fig. l an electrode holder on which the invention may be mounted. This holder comprises a pair of shank-forming portions 8 and 9 which are positioned with concave portions directed 'toward each other to provide a barrel or well in which the bared end I0 of the conductor- II may be secured. Projecting outwardend of the Vbarrel sections are spring jaw-forming members 8 and 9', a bolt I2 being projected through these members for adjustment purposes.

view taken on line 2 2 View of an insulating adjacent their ends are plates I3 and I4 of suitable insulating material. An insulating handle I5, formed from bre or the like, is mounted in embracing relation on the shank-forming portions 8 and 9.. The jaws are positioned in superimposed relation and normally held in close approach to each other so as to grip an'electrode Wire therebetween, the jaws being of sufficiently resilient material to accomplish this. In order to spring the jaws apart for insertion of the Wire therebetween I provide a stirrup embodying the lower or bottom bar I6, the top bar II and the side bars I8 and I9. Projecting upwardly and angularly from the top'bar I'I is a prong or rod 20 of spike-like structure, this rod being formed integral with the rest of the stirrup. As illustrated, one of the jaws 9 is extended through the stirrup so that the bottom bar I6 will, when the stirrup is rocked, operate as a cam for spreading the jaws apart as shown in Fig. 1, the jaws being illustrated in spread-apart position in Fig.

Mounted on the outerV Vin Fig. 4 or L-shaped as in Fig. 5. In order to the top bar l'i.

Y project.

1 in full lines and in closed position in Fig. V1 in `dotted lines. To insulate the outer face of the side bars E3 and i9 and top bar i-I utilize a structure which may be U-shaped as shown provide the VL-shapedvstructure in Fig. 5 it is but necessary to saw or otherwisecut the U- shaped structure of Fig. 4 centrally across the bight. This structure is formed from a strip of as fibre. 'as- V,Covering "the outer face of the bar isis the leg 22 and the` an- A-gularly .turned portion 22 of this leg servesl to..

engage and cover a portion oi the outer face of Covering the outer face l ofttie side bar i8 is the leg ''having the angularly turned portion 23 covering a portion'oi the outer face of the top bar H, each of these portions 22? and 23 having formed in their opposing end ifaces a notch 2s, so thatas thejaws 22 and 23' are `20 brought substantially assessment with ther 'the' bilfsssd'iwisesis will @im assos ills' 2i ih fsush 'Whfhihsfrsd Qrprws 255 Fis. 4 the structure may' @termed @sensu 'or shapes construction, se ses@ and 23 eah'having'openings 2i formed therein and thebight 25 of the U-shaped structure havifie'spssis fsrfsd there? iysilitesltliis highs-2i cliamsitisallv'sf the 'sessies 265'- a pair so of structures illustrated in Fig. 5 are thus` igrined': Whsnrlsd in position as: shown-insigscrews E? are projected through openings 25 and tljireadw-` ed into the side bars 5S and iii sorthat the struc- As shownV 25 ture is securely held in position. 1The''st ,ruture illustrated in Fig. fl may be r-nounted ogn the up'bvprojecting the prong or rod 23 thwugh opening 2PK, and sliding the Ushaped struture downwardly onto thestirrup. when the screws 'sil are s @sufed'is 'posities @melons of shsssdsilfusture or@ the weer facs of. the baril WOUlCllsf prevents f lisis. 'also the case Whse the Lfsllsssol Dietas. in die. 5, are used-.

It vvill/ lbe noted that the tube @u Whih is fsfls 9i insulating, material s'iosslted- @verand sionpftlie prone or rod 2s to; or v Qt hand. grip for appli/ins the-oef; @Query- Pressure to .rods the. strruo- It wsu be Oiled-fillet the lower epd @this tous 2s. termi-. naiss spas-@drie su to the outer raceef, the bar ll- The. spacing Qf; the lowerend ofthe tub e 2 3 from the Oster isce O f the bar il is a distance substantially equal to the thickness of the DGI- tions 22 and f'rlsol'ars tofnorn'ially engagethe outer fisse thereof- Thus. the epd f vids s han@ the tube 21S. seri/esito prevent upward swinging 0 1 bending or tneportions 2 2# ansss'.. .l

In theuse of an electrodelholder oithis type the 'rnernbers Li?. and 2 3- are subjectedito intense. heat `and frequently are burned off, They sometimes are damaged through Contact with other objects. In, the use o i an electrode holder, onlyA one ofthe members 22 or ESjWould -be directed toward the heat. depending upon themen-ner and. custom oi thef'welder in holding his-electrode holder. Should one of the members 2 2: orE becorne damaged. `or burned. so'that it no longer? functions as annsulatng member for the-bars ssior is, .the retaining sreiv mavzbe. removed and, ii the form shown inEig. 4; is usedbthebighti E may be sltted dianidetricallly of the opening 214;'

"tliiisissltmitiissremoval-ofthe. nation oir-toene sachetsaid youter face of'v moved and replaced without necessitating a disturbance of theY other side, I have also provided an insulatinginember,having a portion insulatfingthe outer Vraices of the side-bar and a portion'insulating the outer face of the top Ybar H.

When the portion shown in Fig. 5 is used the notch 2s serves as a means forresisting, through itsengageinent with the'prong or rod 2S, any

tendency to twist or rock the insulating piece.

vThe endoi 'the tube 28 serves as a substantial coverior. the split separating thef pieces 22 and 23'*- Y 'It will be noted from Fig. 2 that these members?? E@ are estsedsdfoevood thelsodfof biossido-har iii. and i9, arlsltherebv @rvs asaflf dtlooal nrc-testigo tast-'6r fb-reigns tif -Cles particularly metal the-lower iaiv at thelocation.Y ofthe-merels '23ans is.. fusiladehs has shown thattl'lis. @eten features although vthe members desired. be terminated Qfthelwerbari@ Y In tir Way I hsvenravided a sss: tive means of .insulating .the s trrrup inisuch'a marmer thatthe insulation se readily ref. moved and rep std What l @la In Combination .with an electrodeholder', va jaw rocking stirruuoi theolass .dsssrihedxhave ngoppssitslvdisposed side bars and :a top-har; means for insulating the outer Yfare. of said sid-e .bars `and said-top barf'eomnrisiog ata-Jair Q i L:

Ci @G sstid -stirrupethe leg oil ie overlying and cover-.ing the d 'han and the:balanee-y of said bodies beine extended' inwardly-toward each shaped bodies. s.

Y 'other for substantially covering the. outer. tace e5.

of said top hantise, opposed feesiioi" the ends-'roi said lisses of, said L shapes oo cuesnavinefa fes cess fortified therein, said bodies,"-Whenl'mounted on'said stirrup, fo :gringa substantialiyy g-.shaped structure; and means iorsecuring-ieither.ot said bodies On'saidzs up.' independently@ .theothen 2.. Ing combination with :an eleetrode holder, a

jaw rocking; Strrups of: tliezclass; described having o ppositely disposed sidebars and a top b'argme sulating means for. ooveringithe. outer iaoes. ofthe said side. bars :embodying 'ay pair 0i members, the legsrthereof overlying and covering the outer; facepitheside bars oiisaid-stirrup and thebase thereof; preotingI inwardly oi and :con-

ering a portionofthe outer face, of said topba'r;v and. means for securing said"` L-shaped' members on said stirrupreacnindependently fir-fthe, othe1:.

3. in combination with an electrode 'l;io'lder, a,

jaw rocking stirrupof thefciass, describedhaving'oppositely; disposed side barsand :atop and provided With a handle, iormingmexnbenpro.-

jecing outwardly. romzsaid toptbar., means. for.V

insul-atingtheouter f aoes of saiduside 4barsand said top bar comprising a pairr'oiA -Li-sha-ped; members of insulating material one portieri' off each oi saidyrnenibers `overlying and coveringthe outer` 'face of: a side.' bar and; the; other. portion. oi' each.

of said members beingfdirected; inwardly tonneslie and covelf'tiiaollter. tace.of-saidJ tonbary'and means for. securingzgsaid: members om saidfstinrup each ndependentlmoi-the other.4

4. In combination with an electrode holder, a jaw rocking stirrup of the class described havy ing oppositely disposed side bars and a. top bar and provided with a handle forming member projecting outwardly from said top bar, means for insulating the outer faces of said side bars and said top bar comprising a pair of L-shaped members of insulating material one portion of each of said members overlying and covering the outer face of a side bar and the other portion of each of said members being directed inwardly to overlie and cover the outer face of said top bar, the opposed faces of said portions of said L-shaped members which overlie said top bar having a notch formed therein for partially embracing said handle-forming member; and means for securing said members on said stirrup each independently of the other.

5. In combination with an electrode holder, a jaw rocking stirrup of the class described having oppositely disposed side bars, a top bar and a handle-forming member projecting outwardly from said top bar, means for insulating said stirrup comprising a strip of insulating material bent between its ends to provide a substantially U-shaped member'embracing said stirrup, the bight of the U-shaped member covering the outer face of said top bar and the legs of said member covering the outer face of said side bars, said bight having an opening formed centrally therein for reception of said handle-forming member; and a tube mounted on said handle forming member in embracing relation and terminating at one end substantially in engagement with the outer face of the bight of said U-shaped member for retaining the same in close relation to the outer face of said top bar.

6. In an electrode holder, a jaw rocking stirrup of the class described having oppositely disposed side bars, a top bar and a handle-forming member projecting outwardly from the top bar, means for insulating the stirrup comprising a strip of insulating material bent between its ends to provide angularly extending portions overlying and covering the outer face of the side and top bars of the stirrup, and a tube of insulating material extending over the handle member and'embracing the outer face of one of the angularly extending portions of the insulation strip to retain the same in close relation to the outer face of the top bar of the stirrup.

THOS. S. DONNELLY. 

